3-D chips getting cool

PORTLAND, Ore. ó Georgia Institute of Technology has received a three-year $2.9 million contract, with industry partner Rockwell-Collins, to develop liquid evaporation cooling techniques for three-dimensional chip stacks from the Defense Advanced Research Projects Agency (DARPA) as part of its Intrachip/Interchip Enhanced Cooling (ICECool) program in DARPA's Microsystems Technology Office.

The researchers are already developing "schemes that can address high power on the whole chip coupled with very high-power dissipation areas that are only a few millimeters square," said professor Yogendra Joshi, the project's principal investigator. Also participating in the project are professors Muhannad Bakir, Andrei Fedorov and Suresh Sitaraman.

The non-uniform cooling system will use special liquid-evaporation techniques that can dissipate one kilowatt per square centimeter over an entire integrated circuit and handle five kilowatts per square centimeter on millimeter-sized hot spots. The researchers will also characterize different coolants as well as develop detailed models for how liquids boil at the micron scale.